“Yahweh spoke to Moses. ‘Now the tenth day of this seventh month is the Day of Atonement. It shall be a holy convocation for you. You shall deny yourselves and present Yahweh’s offering by fire. You shall do no work during that entire day. It is a day of atonement, to make atonement on your behalf before Yahweh your God. For anyone who does not practice self-denial during that entire day shall be cut off from the people. Anyone who does any work during the entire day such a one I will destroy from the midst of the people. You shall do no work. It is a statute forever throughout your generations in all your settlements. It shall be to you a Sabbath of complete rest, and you shall deny yourselves. On the ninth day of the month at evening, from evening to evening you shall keep your Sabbath.”
10 days after the festival of trumpets, the Day of Atonement or Yom Kippur takes place. You have to deny yourselves and present Yahweh’s offering by fire. You do not do any work on this day, but practice self-denial. This punishment is very severe. Yahweh would destroy you. See chapter 16 for more details about the ritual with the scapegoat for this feast of atonement. This atonement Sabbath goes from evening to evening.